These little guys are the answer to keeping your boy in his CB-6000, CB-3000, or "Curve" chastity devices, even if he's got to get through a metal detector. With unique serial numbers printed on each one, these all plastic locks will not come off without being cut or otherwise destroyed. When he comes home, you compare the serial number with the one he started with and see if you have to get out the big whip or the bigger whip.